Sorry, i just have to do it, call me a weeaboo for swapping out the "Sisters" part in the title, and sorry for not putting in the standard emo hair, almost every sisters model/art look like an identical clone, maybe that hairstyle is part of their standard armor......

the whiteness for the Martyred Rose (the most commonly used sister in the fluff) was a dye because they mourned the loss of their original Cannoness... I don't know why all the others have white hair too.

If I was you, I would added a little imperial crybaby fleeing from an ork marauder that screams: "Oneechan, help me!". Something like: "My Onechan of Battle can't be so cute"... Ok, today was a long day, bear with me. Great work as always!